I got an answer I like from some Jehovah's Witnesses who had set up a portable stand on the street to hand out literature. They told me God permits the devil to confuse us because just being told the truth isn't enough. The truth has to sink in. I think that, even to a committed atheist, it's obvious that our species is not making it. We're completely failing to survive, let alone prosper. And that has been obvious to anyone who has eyes to see, for some centuries now. So maybe it is all really God being patient with us dummies until we clue in that we need Him. And when we do clue in, if ever, then there will be no more evil in the world because God will no longer permit it.
What I don't like is the JWs' inconsistency in telling people God's word because telling people stuff, as I said above, accomplishes nothing by itself. The word has to sink in and become real to us, and each of us must do that alone for himself.
What do people think?